Wireless communication systems and networks are used in connection with many applications and devices, including for example, portable communication devices (PCDs) (e.g., cellular telephones), portable digital assistants (PDAs), laptop computers, or any suitable device that is capable of communicating with a wireless network. One significant benefit that wireless communications networks provide to a user of portable communication devices is to allow the user mobility to travel within and between networks.
Many different modes or types of wireless communications systems have been developed. These modes include GSM (Global Systems for Mobile Communication) (which may include WCDMA (Wideband Code Division Multiple Access)), CDMA (Code Division Multiple Access), WLAN (Wireless Local Area Network, based on the IEEE 802.11 standard), UMTS (Universal Mobile Telecommunications System), WiMAX (based on the IEEE 802.16 standard), and the like. Different modes of communication may be provided in different geographic areas or by different communication service providers in the same geographic area. Multi-mode PCDs, which are capable of communicating over two or more different modes of networks, are becoming more common. Because such multi-mode PCDs enable users to communicate with different types of systems, users may therefore be able to communicate in many different geographic areas.
When a user travels to a new geographic area with a PCD, the PCD will typically establish communication with one of the available systems in the new geographic area. Two or more different communication systems with which the PCD may communicate may be available in the new geographic area. As such, the PCD may select one of the communications systems and establish communication with the selected system. The PCD will typically use a predefined method for determining which communication system to select. Typically, each different mode of communication may use a different method for determining which communication system to select. Such methods may use a priority list, such as the Preferred Roaming List (PRL) used in CDMA systems, that is stored in the PCD. The priority list may be arranged by geographic area, and typically comprises a list of systems with which the PCD may establish communications depending on availability of each system. As the PCD enters a new geographic area, the PCD will typically attempt to establish communications with the first system on the priority list. If the first system on the priority list is not available, the PCD will typically attempt to establish communications with the second system on the priority list. The PCD will typically cycle through the priority list, attempting to establish communications with each successive system on the priority list, until the PCD is able to establish communications with one of the systems on the priority list. The systems that are contained in a priority list may vary based on the particular geographic area, the communication service provider for a particular PCD, and the reciprocal agreements between the communication provider for the particular PCD and other communication providers (e.g., roaming agreements). The priority list is typically stored in each PCD, and may be updated via the over-the-air service provision (OTASP). Each method of determining which communication system to select typically has a goal of ensuring basic voice service for the PCD.
When a user of a multi-mode PCD travels to a new geographic area, the multi-mode PCD may be able to establish communications with a number of different systems corresponding to each different mode. For example, the user may have a PCD capable of communicating using GSM, CDMA, and UMTS. There may be several available GSM systems, several available CDMA systems, and several available UMTS systems in the area. Currently, the user would typically need to select which mode the user would prefer to use to establish communications. The PCD would then use the corresponding method of determining with which system to establish communication within the selected mode. There is a proposal to establish what may be termed a mode priority list. The mode priority list may be used by the PCD as an alternative to allowing the user to select the desired mode. The mode priority list may comprise a list of modes that the PCD is capable of using to communicate. The mode priority list would typically indicate the order in which the modes should be used by the PCD to attempt to establish communication. As the PCD attempts to establish communication within one particular mode, the PCD would typically use that mode's method of determining which system to select (e.g., the priority list). In the example multi-mode PCD described above, the mode priority list may indicate that communication should be attempted with CDMA first, then GSM, and finally UMTS. Typically, the PCD would first attempt to establish communications with the systems on the CDMA priority list (i.e., the PRL). If the PCD is unable to establish communications with any of the systems on the CDMA priority list, the PCD would then typically attempt to establish communications with the systems on the GSM priority list, as GSM is the next mode in the mode priority list. If the PCD is unable to establish communications with any of the systems on the GSM priority list, the PCD would then typically attempt to establish communications with the systems on the UMTS priority list, as UMTS is the next mode in the mode priority list. If the PCD is unable to establish communications with any of the systems on the UMTS priority list, the PCD would then typically attempt again with the CDMA priority list. Even under this proposed new method of determining which communication system to select, the goal would typically still be to ensure basic voice service for the PCD.
While basic voice service may be important to PCD users, many other services may be desired by users and provided by many, but not all, communication service providers. Examples of such services include but are not limited to instant messaging (IM), push-to-talk (PTT), multimedia messaging service (MMS), device management, voice over internet protocol (VoIP), and other voice and data services. When a user travels to a new geographic area, the user may desire to continue using a service, such as MMS, that the user was using in the previous geographic area. As such, the user would prefer that the PCD establish communications with a system that is capable of providing the desired service. However, current methods for determining which communication system to select do not consider the availability of desired services.